He Was Enraged She Texted Another Man – So He Killed Her and Left a Deceptive Post-It Note Behind

An Illinois man who killed his girlfriend and positioned her body to make it seem like she took her own life has learned his fate.

Nathaniel Archuleta, 19, pled guilty to first-degree murder in the death of Mary Halcomb, 20, and was sentenced to 45 years in prison. He will have to serve 100% of his sentence, according to a statement from the Peoria County State’s Attorney’s Office, 

On Sept. 6, 2024, police responded to a house after receiving reports of a woman who shot herself. When they arrived on the scene, they found Halcomb lying in a pool of blood on the stairwell landing with a gunshot wound to her neck, the state’s attorney’s office said. 

Officers pronounced Halcomb dead at the scene but found the circumstances odd, per the SA’s statement. Officers found evidence that appeared inconsistent with a suicide, including a blood trail coming from a downstairs bedroom to the landing where she was found, as if her body had been moved.

In the downstairs bedroom, per the statement, police found a post-it note that read, “I, Mary Elyce Halcomb, promise to never break Nathaniel Archuleta’s heart, and if I do, Nathaniel Archuleta has every right to euthanize me, vice versa, I love you.”

When police questioned Archuleta, he gave conflicting accounts of what happened that night, according to prosecutors. He initially claimed that Halcomb took her own life but then said he accidentally shot her while trying to clean his gun. 

Officers later learned that while in custody, Archuleta had admitted to another inmate that he shot Halcomb after discovering she was texting with another man, the state’s attorney’s office said in their statement. 

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Halcomb’s mother, Ashley Halcomb, told the Peoria Journal Star that she didn’t believe authorities when she found out what happened to her daughter. 

“I went into sheer shock and numbness,” Ashley said to the outlet. “I didn’t want to believe any of it was true.”

Ashley said her and her daughter were very close, per the Journal Star. Since Ashley had Mary at 20 years old, she felt the two of them grew up together. By the time Halcomb became an adult, Ashley saw her daughter as her close friend. 

“We did everything together,” Ashley told the outlet. “She told me everything – sometimes a little bit too much – but I knew she trusted me.”

Ashley told the Journal Star that she didn’t know much about Archuleta, other than her daughter would go to his house frequently. 

“I knew that she would go to his house and (she) was friends with him,” she told the outlet. “But that’s all I know… It feels like a really bad dream.”

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.

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